How to pass parameter to the attachEvent javascript function

Question

I have to pass paramter the validateNum javascript function (eg. num1, num2)

if (num1.attachEvent) {
 num1.attachEvent("onkeypress", validateNum);  
}

How to pass. can i get code sample?

Answer 1

You need to make an anonymous currier:

num1.attachEvent("onkeypress", function() { return validateNum(num1, num2); });  

Answer 2

Aside from SLaks' answer, in ECMAScript 5th Edition implementations you can use the bind method:

num1.attachEvent("onkeypress", validateNum.bind(null, num1, num2));

In implementations that don't support the method you can either use the Prototype JS framework or just add the method to the Function prototype with this snippet:

if (!('bind' in Function.prototype)) {
    Function.prototype.bind= function(owner) {
        var that= this;
        var args= Array.prototype.slice.call(arguments, 1);
        return function() {
            return that.apply(owner,
                args.length===0? arguments : arguments.length===0? args :
                args.concat(Array.prototype.slice.call(arguments, 0))
            );
        };
    };
}